Confession time: I have always been somewhat intimidated by and in awe of microwave electronics. Experts in that field have always struck me as being spookily skilled in the conjuring arts.

In the summer of 1966, I was employed at Sanders Associates in Nashua, NH. One day, I got put on loan from my regular department to work in the Simon Street facility where all kinds of microwave projects were underway. Sanders had a proprietary form of what I saw as stripline, but it was politically incorrect to use that word there. The only acceptable noun was “tri-plate.”

There were efforts going on to develop directional couplers for X-band or 9-GHz service. High-attenuation couplers, loosely-coupled couplers if you will, were already well-established products. Essentially, they looked like this.

Figure 1 This was the structure of a loosely-coupled directional coupler.

The goal was to make much tighter directional couplers. Instead of the coupled signal being 20 dB down from the main line signal, the goal was 6 dB. The structure was to look more like this.

Figure 2 This was the design for a tightly-coupled directional coupler.

This one engineer set about devising a design for a 6 dB coupling. He did all kinds of mathematics; he specified what kind of dielectric board would be used, he specified the copper foil’s dimensions and thickness, he specified the aluminum block in which this structure would be contained, and so on. He really thought he had it aced.

He sent his papers over to manufacturing, who shortly afterward delivered a first piece sample to him for evaluation. The measured coupling was pretty close to the intended 6 dB and the bandwidth of the coupler was better than he had anticipated. That was one really happy engineer, but not for long.

After running all kinds of exhaustive tests and being very pleased with everything he saw, he opened the unit up to inspect the physical innards. He then discovered that the dielectric board was only half as thick as he had called for, and upon making that discovery, this guy went berserk. Shouting expletives at the top of his lungs, he slammed the coupler prototype down to the floor where it bounced around and came to rest under someone’s desk.

This was in August of 1966, approximately a month before the premiere airing of the first episode of Star Trek with the sci-fi popularization of the word “warp,” but this guy had thrown that coupler to the floor at warp speed.

I don’t know if that coupler project was ever a success or not because I was shortly afterward returned to my original department. Frankly, I was quite happy to get back home to Analog Land.

John Dunn is an electronics consultant, and a graduate of The Polytechnic Institute of Brooklyn (BSEE) and of New York University (MSEE).

This start of great, but then what was the point of this article? Must have been over my head.

These essays in Living Analog and elsewhere are brief insights into engineering issues, sometimes into the technology (There is a honey of an article on directional couplers referenced above.) and sometimes into the humanity.

This particular essay is one is of the latter.

I’ve written about the human who gave me falsified thermal rise and fall data, the human who asserted that an oscillating power supply was acceptable because the oscillation frequency was above the specified frequency range for output ripple, the human who handed me an infrared thermometer covered with saliva and ear wax and other humans with still other aberrant behaviors. This temper fit was merely one example of human, is the word “nature”?

I’m not through with that either. There will be more.

I guess I missed your point. Why was he mad? Who decided to make it thinner? Its like showing a car commercial then a train wreck. How are they related. THIS IS WHAT IS NOT CLEAR TO ME.

The point of the essay is the following.

How the board thickness got to be only half of the intended thickness is anyone’s guess. The answer is long since lost to history. Maybe the engineer’s handwriting was sloppy. Nobody knows.

The point of the essay is to shed some light not just on the technical analytics but on the mind set of that particular engineer. He was so totally invested in the project, so emotionally wrapped up in it that he lost his rational perspective.

I didn’t know him, I never knew his name and I don’t even have any memory of what he looked like. However, given his reaction to what was indeed a setback, I would venture that he would have benefited from the professional attention of a competent mental health professional.

I do not mean to cast ridicule. That scene took place almost fifty-four years ago and I can only hope that the fellow somehow regained his composure and went on to successes.

I have to agree. The story lacks a conclusion. First it seems like it’s going to be an article about the proper design of a coupler, but it is not. Then it seems it is going to be a workplace tale, but that is not concluded satisfactorily. We do not understand why the guy is angry even though the design works.

Evariste, these essays are not application notes. They are merely anecdotal stories, hopefully with insights into thinking processes, whether my own or someone else’s, and sometimes with a related tidbit of technical information. Some measure of empathy for the folks whom I now and then describe could be helpful.

If you want a full-blown treatise on directional couplers, that article I called “a honey” should definitely receive your attention.

So far, Living Analog has two-hundred-thirty published essays, one essay still pending for this month and there are ninety more essays on my hard drive waiting to be submitted. If all of them get accepted for publication, those materials will last thru February 2024.

I intend to carry that through.

I was taught in grade school that a story has a beginning, a middle, and the end. This tale of woe, did not have an END. You might want to review your unpublished tales and ensure that they meet the grade school standard.

To use your structure, Qerqwe, the beginning would be when I got loaned to the microwave department, the middle would be my noticing the development effort that was being devoted to that directional coupler and the end would be my own, and hopefully your own, astonishment at that engineer’s behavior.

Of course if I had the writing skills, let’s say of a Steve Taranovich, these essays would undoubtedly be of a much higher caliber in which case cheap insults would be far less likely. Maybe not zero, but then such things can’t easily be predicted.

I can’t empathize with the character because I don’t understand his motivations, nor even guess at them. Maybe he was going through a divorce? I don’t know.

I think you should punch up this story with a romance. He’s a playboy engineer, and she’s a go-getter engineer in the same department, initially repulsed by her colleague. Let’s say she is played by Katherine Hepburn. No, let’s make it Anne Hathaway. They are both vying for the big promotion at the end of the quarter. She’s the one who sabotaged his design, submitting her own which is superior. They overcome their differences and fall in love. She gets the promotion and he stays at home to raise the baby.

I love it!!! A sequel to Desk Set (1957) with Anne Hathaway in Katherine Hepburn’s role, but who would take over for Spencer Tracy?

I’ll go with Ryan Gosling. I can imagine him seething quietly before he throws the prototype to the floor. Or maybe Justin Timberlake if it’s to be more of a comedy.

You need to be careful around us career RF guys as we can be dangerous hence your story about the engineer throwing a temper tantrum and tossing things around but I have been more of the have fun kind of RF guy as opposed to the throwing temper tantrums type of RF guy.

When I started 30 years ago I worked with another RF guy my senior and we had a new hire who didn’t know much RF who was helping us troubleshooting a receiver circuit inside of a small box with a home brew RF probe that he made.

Upon picking up all kinds of RFI from his probes long leads we told him to shorten up the tips of his probe to about .01 inch and told him to then probe the circuit all the time knowing that the .01″ leads would not reach the circuit trace and nearby ground at the same time all the while waiting to see what he did.

Yes we were devious but the best part was when he started complaining and yelling and screaming about how short his probe was and that his probe was so short that it couldn’t reach inside the darn slot in the box upon which the senior RF guru exclaimed that “that sure sounds like a personal problem” and that he should keep such information to himself which of course went way over his head but it sure did elect laughs from several other engineers nearby.

Like I said you need to have fun as opposed to throwing tantrums, when tantrums come out it’s a sign that you need to change careers.

John, Nice story! I think you sort of posted a riddle here. Something like, “From a technical standpoint., WHY was the tempermental engineer throwing a tantrum?”

If I were to hazard a guess, it was because that half thickness dielectric board meant that the dielectric breakdown of the coupler from input to output was too low, so the design was unusable because of that.

Keep up the good work, Dan

I’m amused (and puzzled) that you wrote you were happy to get back to Analog Land. I always thought of RF as being Analog. Maybe both a subset and a superset of Analog.

Maybe that’s because I grew up with all the engineers around me abandoning Analog for Digital.

Everything in the universe is rate limited by something or by something else. Nothing ever happens in zero time. That’s why I wrote on LinkedIn in my group Analog Developments that “…….ultimately, all designs in every area are analog in nature.”

Somebody once told me of having conducted a job interview and the candidate, when asked about analog skills, replied “Analog is a dying art. Everything is going digital now.”

The year of that interview was 1978. It was for good reason that no job offer was made to that individual.

The fundamental rules of technical writing are:

tell the reader what you are going to tell them

tell the reader what you’ve told them

The basic problem with this and the phase dispersion article is a failure to perform all 3 steps. You left out the first and last.

My BA is in English lit, but I spent my career in seismic oil exploration. So I went from no math to almost nothing but math by way of geology. Electronics is for me just a hobby well suited to an unemployed research scientist who needs a technical challenge to stay sane.

The phase dispersion article should have calculated how much phase dispersion it takes to reduce the amplitude of one of the sidebands by 6 dB. The dispersion is effectively a notch filter at the harmonics of the fundamental.

I think the next sentence after “Analog is a dying art. Everything is going digital now.” should have been considered. I could certainly have said that having spent my career doing state of the art DSP. But in an EE context interview I’d have noted that digital is implemented in the analog domain.

And all that DSP stuff is an exact description of the analog world if you know how to use it properly.

My latest amusement is the problem of in-circuit analog component testing. More specifically compensating for arbitrary parallel components. If you probe a particular part, all the other parts in the circuit have a phase delay associated with their position on the board. If you account for the phase delay you can mathematically eliminate them from the desired measurement. I’m not aware of any analog method for solving that despite it being a purely analog problem.

I’ve started a thread on this on EEVblog if anyone is interested.

https://www.eevblog.com/forum/projects/in-circuit-component-testing/msg3074730/#msg3074730

https://licn.typepad.com/my_weblog/2020/05/unmet-expectations-john-dunn-consultant-ambertec-pe-pc.html

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